Spring for Ring-necked and Alexandrine Parakeets in Haarlem
Today we visited the parakeets of Haarlem (The Netherlands). Spring is in full swing for these birds and their breeding cycle well advanced.
There are two species of parakeet in Haarlem. The first and most numerous are the ubiquitous Ring-Necked Parakeets (Psittacula krameri). A species that is common in the Randstad area that joins The Netherlands mayor cities of Rotterdam, The Hague, Amsterdam, Haarlem and Utrecht in the west. These birds are joined by a closely related parakeet which can only be found wild in the Netherlands in Haarlem and Amsterdam: the Alexandrine Parakeet (Psittacula eupatria).
The two species are so closely related that hybrids of the two occur and the hybrids are fertile. In captivity this phenomenon is often used to transfer colour mutations from one species to the other. One cross with a colour mutant Ring-necked parakeet makes the colour mutation available in the hybrid bloodline. Selective back crosses to the Alexendrine parakeet keeps the colour mutation but in a few generations the birds are morphological equal to the Alexandrines. This same process gave us the red canary, which got its red colour from a cross with the Venezuelan Red Siskin (Spinus cuculatus).
The Parakeets are clearly breeding. Males came in to feed their partners at the nest. Females only came out for a short while to receive the food and to stretch their wings.
Later we went to the roost site where the non breeding population of the two species congregate for the night. In the park where the birds breed the two species were clearly distinguishable by the deeper voice of the Alexandines, for which you would be forgiven if you mistook them for an Amazon parrot on voice alone. But at the roost this distinction was les clear. Some of the bigger parakeets sounded like Ring-necked parakeets. Photographs of some of these birds reveal they have a brown spot on there wings in contrast to the a red spot that a Alexandrine parakeets ought to have. These birds are hybrids between Alexandrine and Ring-necked parakeets.
The hybridisation of the two species raises many questions. Why is it occurring? Is it because not all the Alexandrine parakeets can find a mate? What will be the effect on the Parakeet population as a whole. Will there be a new species of parrot developed in Haarlem that retains traits of both parent species or will one species win over the other and will most or all genes of one of the species be filtered out of the population. Time will tell.
The total population of parakeets counted at the roost were 81 birds. 14 Of which were the size of Alexandrines.